Reticulated vitreous carbon from polyurethane foam–clay composites

Reticulated vitreous carbon foams were prepared by carbonizing polyurethane precursor foams which were first infused with furfuryl alcohol. The cell size and the fraction of open cells of the precursor foam were controlled by the addition of clay in the polyurethane foam formulation. Addition of clay permitted control of the cell size of carbon foams. The higher open cell content in foams with clay permitted uniform infusion of furfuryl alcohol in the precursor, and thus more uniform carbon foams of higher density. These foams had a lower electrical resistance as compared to foams without clay.